Now that ReadMemStats is fast (CL 34937), CL 36791 is not so
necessary, and causes confusion. See #20863

This was already partially reverted in CL 46612 but missed two of the
spots.

Fixes #20863

Change-Id: I1307a0f7b1f9e86e8b6ceaa6a677f24f13431110
Reviewed-on: https://go-review.googlesource.com/47350Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #20834.

Change-Id: Ic60000db6b8ae489a5cedbdc938d9ca1dc34c6d4
Reviewed-on: https://go-review.googlesource.com/47151Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Updates #18581
Updates #20858

Change-Id: I6b5ce0e255a42c028d46815fff5a5aca68690fd9
Reviewed-on: https://go-review.googlesource.com/47254
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #20839.

Change-Id: I125460c5da09b7fa0cf470ff5be436f8d650cde7
Reviewed-on: https://go-review.googlesource.com/47253
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Document that the byte value returned by ReadByte() is meaningless
if its error != nil. Because io.Reader and io.ByteReader are similar in
name, this CL aims to clear up any ambiguity surrounding the returned
values, particularly where io.Reader is allowed to return both a
non-zero number of valid bytes and err == EOF.

Fixes #20825

Change-Id: I3a23c18c80c471c0caae3b4d2f6f8e547da0bed9
Reviewed-on: https://go-review.googlesource.com/46950Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

FreeBSD 9.3.
Add Linux arm64. (required second line)
Clarify glibc requirement now that we have second line in notes.
OS X to macOS

Updates #20850

Change-Id: I684d464ed32a072081726b7c805a346c22c42f97
Reviewed-on: https://go-review.googlesource.com/47252Reviewed-by: Ian Lance Taylor <iant@golang.org>

This reverts commit df68afd0 (https://golang.org/cl/33276)

Reason for revert: made other benchmarks worse

Fixes #20693 (details)
Updates #17914
Updates #10335

Change-Id: If451b620803ccb0536b89c76c4353d2185d57d7e
Reviewed-on: https://go-review.googlesource.com/47211
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

Apparently, "all such calls must happen" means that the t.Run call
must *return* before the outer test function returns, or the calls
will cause a data race on t.ran.

Clarify the docs.

Fixes #20339

Change-Id: I191a9af2a9095be1e0aaf10b79c30e00a9c495cb
Reviewed-on: https://go-review.googlesource.com/47150Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

TestInterfaceHardwareAddrWithGetmac was panicing when getmac returned
multiple network cards.

Change-Id: I6fefa5a4910bce805b4cd9c09f94bd56c9682b9e
Reviewed-on: https://go-review.googlesource.com/47190Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Updates #17686
Fixes #20848

Change-Id: I35d58c7d1aa74d3e7867124070e27c787d444b04
Reviewed-on: https://go-review.googlesource.com/47210Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Apply code review suggestion from CL 46715.

The block is doing more than just checking len(r.certs) == len(tc.cns).
It also verifies that certificate common names match.

Change-Id: I28d6926a5da48bd8f6c80aa5e5a1ed6d4990f845
Reviewed-on: https://go-review.googlesource.com/47132Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Updates #20587

Change-Id: I08377281270631ee08cd05ba835aa698ca23fa56
Reviewed-on: https://go-review.googlesource.com/47092
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #19635

Change-Id: I85e725dbc85843afd0f4d82f5127fecacc1cb524
Reviewed-on: https://go-review.googlesource.com/47090Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #19794

Change-Id: I462cbc432fe9d4a9e6e79a9833b0013d82a0780e
Reviewed-on: https://go-review.googlesource.com/47093Reviewed-by: Ian Lance Taylor <iant@golang.org>

Updates http2 to x/net/http2 git rev d4223d6710a for:

    http2: refund connection flow control on DATA frames received after reset
    https://golang.org/cl/46591

Fixes #46591

Change-Id: I5e6999599e921fed279c6d29ae77439191e99615
Reviewed-on: https://go-review.googlesource.com/47096
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Tom Bergan <tombergan@google.com>

And some double space after period cleanup while I'm here.
I guess my previous regexps missed these. My next cleaner should
probably use go/ast instead of perl.

Updates #20221

Change-Id: Idb051e7ac3a7fb1fb86e015f709e32139d065d92
Reviewed-on: https://go-review.googlesource.com/47094Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

Fixes #19713

Change-Id: Id1ca61b35bca2a4bea23dd64c7fb001a3a14fd88
Reviewed-on: https://go-review.googlesource.com/43512Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #20837.

Change-Id: I266519c26c8849da267b77e11abe7734d8275112
Reviewed-on: https://go-review.googlesource.com/47074Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Currently the execLock is a mutex, which has the unfortunate
side-effect of serializing all thread creation. This replaces it with
an rwmutex so threads can be created in parallel, but exec still
blocks thread creation.

Fixes #20738.

Change-Id: Ia8f30a92053c3d28af460b0da71176abe5fd074b
Reviewed-on: https://go-review.googlesource.com/47072
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Currently runtime.rwmutex is written to block the calling goroutine
rather than the calling thread. However, rwmutex was intended to be
used in the scheduler, which means it needs to be a thread-level
synchronization primitive.

Hence, this modifies rwmutex to synchronize threads instead of
goroutines. This has the consequence of making it write-barrier-free,
which is also important for using it in the scheduler.

The implementation makes three changes: it replaces the "w" semaphore
with a mutex, since this was all it was being used for anyway; it
replaces "writerSem" with a single pending M that parks on its note;
and it replaces "readerSem" with a list of Ms that park on their notes
plus a pass count that together emulate a counting semaphore. I
model-checked the safety and liveness of this implementation through
>1 billion schedules.

For #20738.

Change-Id: I3cf5a18c266a96a3f38165083812803510217787
Reviewed-on: https://go-review.googlesource.com/47071
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Prevent possible goroutine rescheduling to another P between
Put and Get calls by locking the goroutine to OS thread.

Inspired by the CL 42770.

Fixes #20198.

Change-Id: I18e24fcad1630658713e6b9d80d90d7941f604be
Reviewed-on: https://go-review.googlesource.com/44310
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

"Forward declaration" suggests that declarations must precede calls.

Change-Id: I1b3a26b58f52a39bc11d75696df928a6b66c7313
Reviewed-on: https://go-review.googlesource.com/47073Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

If the only way the user indicates they want alloc stats shown
is via ReportAllocs, we don't know that until benchFunc is run.
Therefore, StopTimer's ReadMemStats will return incorrect data
for single cycle runs since there's no counterpart ReadMemStats from
StartTimer that initializes alloc stats.

It appears that this bug was introduced by CL 46612,
"testing: only call ReadMemStats if necessary when benchmarking"

Fixes #20590

Change-Id: I3b5ef91677823f4b98011880a3be15423baf7e33
Reviewed-on: https://go-review.googlesource.com/46612Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Updates #20836
Updates #19339
Updates #19652
Updates #20835
Updates #16511
Updates #10166
Updates #8574

Change-Id: If9a7f560489f1a8d628dafab227925bd8989326e
Reviewed-on: https://go-review.googlesource.com/47036Reviewed-by: Ian Lance Taylor <iant@golang.org>

Change-Id: Ibbb89c01f3e812a0602961f959672fcb6523449b
Reviewed-on: https://go-review.googlesource.com/47031
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Updates #20587

Change-Id: If35868345d9697d4afa2e9c19b85e01d94c87908
Reviewed-on: https://go-review.googlesource.com/47034Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

The test added for issue #18146 exposed a long-existing bug in the
Solaris port; notably, that syscall.Exec uses RawSyscall -- which is not
actually functional for the Solaris port (intentionally) and only exists
as a placebo to satisfy build requirements.

Call syscall.execve instead for Solaris.

Fixes #20832

Change-Id: I327d863f4bbbbbb6e5ecf66b82152c4030825d09
Reviewed-on: https://go-review.googlesource.com/47032
Run-TryBot: Shawn Walker-Salas <shawn.walker@oracle.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

os.Chmod returns an error when passed a long path (>=260) characters on
Windows. CL 32451 fixed most file functions in os. This change applies the
same fix to os.Chmod.

Fixes #20829

Change-Id: I3270db8317ce6e06e6d77070a32a5df6ab2491e0
Reviewed-on: https://go-review.googlesource.com/47010Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

A common task is trying to get today's date in the local time zone
with zero values for the hour, minute, second, and nanosecond fields.
I tried this recently and incorrectly used Truncate(24*time.Hour),
which truncates based on a UTC clock, and gave me 5pm Pacific time
instead of midnight Pacific.

I thought it would be helpful to show a "correct" way to do this.

Change-Id: I479e6b0cc56367068530981ca69882b34febf945
Reviewed-on: https://go-review.googlesource.com/46833Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #20830.

Change-Id: I18178064c955ad8d259df05ee954075ae42909b0
Reviewed-on: https://go-review.googlesource.com/47030Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Should use CMPL instead of CMPQ.

Fixes #20811.

Change-Id: I610d487949c2c8a08b3743656149069d931a51bb
Reviewed-on: https://go-review.googlesource.com/46870Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

t.Sub(u) would be -20 milliseconds.
The right computation is u.Sub(t), but rewrite to be even clearer.

Thanks to Karsten Weiss for catching this.

Change-Id: I6e274d69b0301840d57c5c65bf4114da0d33bf10
Reviewed-on: https://go-review.googlesource.com/46971
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

It should be $HOME/go instead of $HOME/work

Change-Id: I22e0a89deff30f935c3e25a237d6c0c161103339
Reviewed-on: https://go-review.googlesource.com/46890Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Updates #20821

Change-Id: I77a5b9a3bbb931845ef52a479549d71069af9540
Reviewed-on: https://go-review.googlesource.com/46913
Run-TryBot: Shawn Walker-Salas <shawn.walker@oracle.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Prior to this change, if the Writer needed to use the PAX format, it would
output a USTAR header with an empty name. This should be okay since the PAX
specification dictates that the PAX record for "path" should override the
semantic meaning of any of the old USTAR fields.

Unfortunately, the implementation of tar on OpenBSD 6.1 is too strict with
their handling of PAX files such that they check for the validity of this
bogus field even though the PAX header is present.

To allow Go's Writer output be parsible by OpenBSD's tar utility,
we write a best-effort (ASCII-only and truncated) version of the original
file name. Note that this still fails in some edge-cases (for example,
a Chinese filename containing all non-ASCII characters). OpenBSD should really
relax their checking, as you honestly can't always expect a sensible path
to be generated when USTAR cannot handle the original path.

Fixes #20707

Change-Id: Id7d77349023d2152d7291d582cd050b6681760e4
Reviewed-on: https://go-review.googlesource.com/46914
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

clang can emit some dwarf.VoidType which are wrapped by multiple
dwarf.TypedefType. We need to unwrap those before further processing.

Fixes #20129

Change-Id: I671ce6aef2dc7b55f1a02aec5f9789ac1b369643
Reviewed-on: https://go-review.googlesource.com/44772Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Also reword the testing/quick.Config field docs to conform to the
normal subject-first style. Without that style, godoc links
/pkg/testing/quick/#Config.Rand to the wrong line, since it doesn't
recognize the preceding comment as necessarily being attached.

Fixes #20809

Change-Id: I9aebbf763eed9b1ab1a153fa11850d88a65571c6
Reviewed-on: https://go-review.googlesource.com/46910Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #20810

Change-Id: I09365b2db50c41aa3383dd730859b6f2cdb78e63
Reviewed-on: https://go-review.googlesource.com/46836
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

If the LHS is unassignable, there's no point in trying to make sure
the RHS can be assigned to it or making sure they're realizable
types. This is consistent with go/types.

In particular, this prevents "1 = 2" from causing a panic when "1"
still ends up with the type "untyped int", which is not realizable.

Fixes #20813.

Change-Id: I4710bdaac2e375ef12ec29b888b8ac84fb640e56
Reviewed-on: https://go-review.googlesource.com/46835
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>

Since Reader.Peek potentially reads from the underlying io.Reader,
discarding previous buffers, UnreadRune and UnreadByte cannot
necessarily work.  Change Peek to invalidate the unread buffers in all
cases (as allowed according to the documentation) and thus prevent
hiding bugs in the caller.

Fixes #18556

Change-Id: I8d836db7ce31c4aaecb4f61c24573b0332bbf30d
Reviewed-on: https://go-review.googlesource.com/46850Reviewed-by: Robert Griesemer <gri@golang.org>